App that reads your mood and fights cravings put to the test

This study tested a smartphone app designed to help people with opioid addiction by sending helpful messages at just the right moment. Nine adults who used heroin or other opioids carried a phone that beeped four times a day to ask about their mood and activities, then showed a message based on their answers. The goal was to see whether different types of messages (like problem-solving or mindfulness) worked better in different situations. The study was terminated early, so the findings are limited.